Process of treating bituminous material



plurality of layers of an Patented Jan. 15, 1929. V

UNITED STATES PATENT OFFICE.

MARK RAY CONE, OF SUDBROOK PARK, MARYLAND, ASSIGNOR, BY MESNE ASSIGN-MENTS, TO THE UNION TRUST COMPANY, OF CLEVELAND, OHIO, A CORPORATION OFOHIO.

PROCESS OF TREATING BITUMINOUS MATERIAL.

No Drawing. Application filed October 24, 1921, Serial No. 510,129.Renewed August 2, 1928.

This invention relates to a process for the treatment of bituminousmaterials, for example, asphalt, pitch, hydrocarbon residues or mixturesthereof, to render the same completely miscible in water without theadmixture of any emulsifying agents.

. The invention relates particularly to an improved process whereby thebituminous material or substance, such as asphalt, pitch,

hydrocarbon residues or mixtures thereof, may be stored for anindefinite period or transported from place to place in a conditionwhich will permit the same to be spread While at ordinary atmospherictemperature upon the surface to be covered, such as a roof, a wall or aroadway in a layer or a desired thickness Without local treatment y theapplication of heat or without any change whatever except the additionof a suflicient quantity of water to produce the desired flow of thematerial.

The invention consists broadly in treating a bituminous substance tosubdivide the same into minute particles approximating to some extent acolloidal state, and then subjecting these particles to a treatmentcausing the same to set and harden in such a way that "the particleswill be of substantially .uni-

form consistency throughout, so that the particles will not readilycoalesce. The invention further consists iii-treating the 'bituminousmaterial so that it may be transported for long distances and maintainedfor considerable periods of time in a semi-solid condition having arelatively small amount of additional weight by reason of the addedmoisture but which will be miscible with water at ordinary temperatureswithout further treatment and adapted to form layers of any desiredthickness.

The invention further consists in provid .ing a product 1n the form of abituminous paste or cement that is semi-solid and plas- 'tic, capable ofbeing maintained in this condition for indeterminate periods of time andof being spread in layers or formed into shapes in molds or dies, whichwill coalesce new and novel details and features of opera;

treatment of bituminous substances hereinafter set forth and claimed.

The bituminous substances to be treated such as asphalt, pitch, mineraloil residues and mixtures thereof, all of whichare commonlygrouped-under the generic term of bitumen, are first heated to atemperature above the fusingpointso as to convert the same to arelatively thin fluid. The material may then be passed through a sprayeror atomizer of any preferred or well known constructiomwhich subdividesthe same into a state ofsubdivision which with respect to the greaterpart of material handled ap proximates a colloidal state of coarsedispersion. These minute particles are then subje ted to the action of amoving body of fluidas, for example, to a current of air or a body ofwater in motion, whereby the particles are dispersed with a graduallyincreasing velocity which will further subdivide the same and normallyprevent the same from coming into contact with each other. Preferably acurrent of air is employedhaving its movement continuous over a smoothsurface and accelerated in a direction away from the point of sprayingor atomization. In case a body of liquid is used, it may be caused tohave a rotary movement within cylindrical confining walls and propelledby any suitable means such as a blade propeller which will give thecentral portion a greater velocity of rotation than the outer portionwhere the sprayed material may be supplied.

The fluid is maintained at a temperature below the fusing point of thematerial but well above the solidifying point, so that the coolingeffect upon the particles during this step of the process will berelatively slow. For example, if the material is heated to a temperatureof l80 F,, then the dispersing fluid would be maintained approximatelyat 140-F.

After being subjected to the action of the dispersing fluid for a periodof time sufficient to permit the surface of the particles to set orharden sufiiciently to lirgit and prevent coalescence it brought intocontact, the particles are then immersed in a non-solvent body ofliquid, preferably water,

which is maintained at a temperature somewhat below the temperature ofthedispersing fluid,for example, at 120 'F.

This liquid may be conducted to any suitable container, such as asettling tank or vat, and the contents allowed to cool slowly toatmospheric temperature. During this period the particles graduallysettle out upon or toward the bottom of the tank leaving a quantity ofsupernatant liquid substantially free of particles, which is thenremoved. Subsequently an additional quantity of the liquid is drainedoff until the residue or precipitate is in a semi-liquid or a fiocculentcondition adapted to be transported and spread upon a surface to becovered. As long as this product is kept in a moist condition, theparticles on account of their character and previous treatment will notcoa esce or coagulate but'each particle will retain its identity and themass as a'whole will be readily miscible in water. If the mass isallowedto become dry, however, or if the material is spread in a layerand the water permitted to evaporate, the particles will coalesce toform a close, compact, co-

herent substance resembling in its physical and chemical characteristicsthe original material from which it was produced.

By means of this process I produce a product comprising bitumen in theform of very finely-divided particles which, so long as a minimumua'ntity of moisture remains adsorbed on t e surface, .will be stablethroughout the range of ordinary atmospheric temperatures, which willreadily coalesce, however, upon the removal of themoisture to form thecharacteristic bitumi-v nous material.

Such a product may be prepared at a central point and distributedthroughout a wide area without requiring or employing plants fortreatment or preparation at the place of local application, where it maybe spread at normal temperature in ogie'or more layers of desiredthickness, either-with or without admixture of sand, stone or fibrousmaterial and without any modification or treatment except the additionof such amount of water as'may be required to give the neededplasticity.

The adaptation of standard and well known forms of apparatus and may bepracticed commercially for the treatment of either large or smallquantities of material.

Although I haveshown and described and have pointed out in the annexedclaims, certain novel features of my invention, it will be understoodthat various omissions, substitutions and changes in the several stepsof my process and in itsoperation may be made by those skilled in theart without departing from'the spirit ofmy invention.

Having thus described my invention, I claim:

1. In the art of treating bituminous material 'to form a plastic mass,the process which consists in spraying the material at a temperatureabove the'fusing point to subdivide the same into fine particles,prevent? ing contact between the said particles until the surfacesthereof have cooled below the melting'point, immersing said particles inheated water, cooling the same gradually to normal atmospherictemperature and removing the water until the material forms a moist,plastic paste.

2. The process of treatingbituminous material to form a plasticsubstance capable of rocess may be carried out by the being spread coldin a thin layer at normal temperature as a surface coating whichconsists in spraying the melte'd bituminous material into a moving bodyof fluid to hold the particles out of contact with each other and hardenthe surfaces of the same, slowly cooling the particles with water andallowing the particles to settle as a flocculent paste, removing theexcess water, spreading the paste over a surface and permitting theadsorbed liquid to evaporate, thereby to form a dense, homogeneouscoating impervious to Water. 7

Signed at Pikesville, in the county of Baltimore and State of Maryland,this 12 day of Oct, A. D. 1921.

MARK RAY CONE.

